(1) Field of the Invention:
This invention relates to a method of producing shikonin.
(2) Description of the Prior Art:
Purple shikonin is a foundamental member of the purple pigments, which is extracted from violet root (Lithospermum erythrorhizon, Japanese name "Shikon") since the old ancient times in the orient. It is not only famous as a "Shikonzome" (shikon-dyed cloth) as included in the treasure of the Shosoin, a Japanese ancient temple, but also is applauded as an ointment for tumor, scald, hemorrhoids and the like owing to its antipyretic and alexipharmic actions. Shikonin is originally known as a famous Chinese medicine as described in a botany of Honzokomoku from old times.
It has been found that shikonin is effective as an antibacterial substance. Recently, shikonin has also been found to be effective as an anticancer agent.
Shikonin is very low in toxicity and is easily used in the coloration of wines. However, due to its scarcity in Japan, it has to be imported. It is regretable that this compound has not been successfully synthesized up to now.